GATES EMH991 Engine Crankcase Vent Valve

( Brand: Gates ), ( Manufacturer Part Number: EMH991 ), ( Manufacturer Warranty: 90 Day ), ( Type: Engine Crankcase Vent Valve )

Review GATES Engine Crankcase Vent Valve

The **Gates EMH991 Engine Crankcase Vent Valve** is a high-performance, precision-engineered component designed to optimize airflow and pressure regulation within the crankcase of high-output and turbocharged engines. This advanced vent valve plays a critical role in maintaining proper crankcase pressure, reducing blow-by gases, and preventing oil leaks while enhancing overall engine efficiency. Crafted from durable materials, including high-quality rubber and reinforced metal components, the EMH991 is built to withstand extreme temperatures, high pressures, and the demanding conditions found in aggressive driving scenarios, including drag racing, street tuning, and heavy-duty applications. Its unique design incorporates a spring-loaded mechanism that dynamically adjusts to varying engine loads, ensuring optimal ventilation without allowing excessive oil vapor or contaminants to escape into the intake system. This not only protects engine internals from carbon buildup and premature wear but also helps maintain peak performance by preventing vacuum leaks that could disrupt combustion efficiency. Ideal for use in engines equipped with turbochargers, superchargers, or forced induction systems, the Gates EMH991 is a direct replacement for OEM crankcase vent valves, offering improved reliability and longevity compared to standard aftermarket alternatives. Whether installed in a high-revving V8, a turbocharged inline-six, or a nitrous-injected performance engine, this valve ensures a cleaner crankcase environment, reduces oil consumption, and supports the longevity of seals, gaskets, and other critical components. Built to meet the rigorous demands of performance enthusiasts, the Gates EMH991 is a must-have upgrade for anyone seeking to maximize engine protection and efficiency in extreme driving conditions.

### **Pros and Cons of buying a Gates EMH991 Engine Crankcase Vent Valve**

1. **Improved Engine Breathing** The EMH991 is designed to optimize airflow in the crankcase, reducing backpressure and improving engine efficiency, especially in high-performance or turbocharged applications.

2. **Enhanced Oil Control** It helps prevent oil leaks and blow-by by maintaining proper crankcase pressure, which is critical in engines prone to oil consumption or crankcase ventilation issues.

3. **Compatibility with Modern Engines** Gates is a reputable brand that produces high-quality aftermarket components, and the EMH991 is designed to fit many common engine applications, including those with turbochargers or forced induction.

4. **Durability and Performance** Made from high-quality materials, this valve is built to withstand high temperatures and pressures, reducing the risk of failure over time.

5. **Easy Installation** Designed for straightforward replacement, it can often be installed without major modifications, making it a convenient upgrade for DIY enthusiasts.

6. **Reduced Carbon Buildup** Proper crankcase ventilation helps minimize carbon deposits in the intake system, which can improve throttle response and fuel efficiency.

7. **Warranty Support** Gates offers warranties on their products, providing some assurance against defects or premature failure.

1. **Cost** Compared to generic or OEM replacement valves, the Gates EMH991 is a premium product, which may be more expensive than budget alternatives.

2. **Potential Overkill for Stock Engines** If the engine is not modified or heavily stressed, the benefits of this valve may not be significant enough to justify the cost.

3. **Installation Complexity in Some Cases** While generally straightforward, some applications (especially those with complex crankcase layouts or additional modifications) may require careful handling during installation.

4. **Limited Longevity in Extreme Conditions** In highly aggressive driving conditions (e.g., heavy towing, extreme turbo boost, or prolonged high-RPM use), the valve may wear out faster than expected, requiring replacement sooner than anticipated.

5. **Compatibility Concerns** While Gates provides compatibility lists, some engines or aftermarket modifications may not align perfectly, leading to potential fitment issues or reduced effectiveness.

6. **No Major Performance Gain for Stock Engines** If the engine is not modified or running under stress, the improvements in airflow may be negligible, making the upgrade less impactful.

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### **Conclusion**

The Gates EMH991 Engine Crankcase Vent Valve is a well-engineered, high-quality component that offers tangible benefits for modified or high-performance engines, particularly those with turbochargers or forced induction. It excels in improving oil control, reducing backpressure, and minimizing carbon buildup all of which contribute to better engine longevity and performance.

However, for stock or lightly modified engines, the cost may not be justified unless specific issues (such as oil leaks or excessive blow-by) are present. The decision to purchase should be based on the engine s application, existing problems, and whether the benefits align with the investment.

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### **Recommendation**

- You have a turbocharged, supercharged, or high-performance engine experiencing crankcase ventilation issues.

- Your engine is prone to oil leaks, blow-by, or carbon buildup in the intake system.

- You are looking for a reliable, high-quality upgrade to optimize engine breathing and longevity.

- You have verified compatibility with your specific engine or modification setup.

- Your engine is stock or runs under mild conditions where the benefits are minimal.

- You are on a tight budget and can find a similarly rated but less expensive valve.

- You suspect the issue may stem from another component (e.g., a failing PCV system) rather than the crankcase vent valve itself.

For most performance-oriented applications, the Gates EMH991 is a strong choice due to its reliability and effectiveness. Always ensure proper installation and consult with a mechanic if unsure about compatibility.

Details:

Engine Crankcase Vent Valve. 53034065AA, EMH991, PCV604, V462. This part fits vehicles made in the following years 2007 ,2008,200 9,2010,2011,2012.

part #: emh991 prices

• $28.15-$35.64

specifications emissyste:

• brand: Gates
• mpn: Emh991
• manufacturer warranty: 90 Day
• type: Engine Crankcase Vent Valve

shipping emissyste:

• class: Economy
• transit: 3-9 Days
• service: Economy
• type: Fixed
• cost: $0.00

offer emissyste:

• started: May 18, 2026
• availability: In Stock
• quantity: 8
• sold: 0
• options: Ship-to-home

returns emissyste:

• time: 30 Days
• paid by: Seller
• policy: Returns Accepted

seller emissyste:

• city: Los Angeles, California
• rating: 98.7%
• # reviews: 2967

general emissyste:

• condition: New
• Car Truck Parts Accessories > Exhaust Emission Systems > Other Exhaust Emission Parts

payments emissyste:

• other
• credit card: Discover
• wallet: Google-pay

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